A known rectangular baler comprises a bale chamber, an oscillating piston in the bale chamber, twine, wire or cord to be wrapped around the formed bale, a knotter device for tying the twine, wire or cord, a twine brake device for setting the tension in the twine.
It is a known problem that at the start of the pressing of bales with a rectangular baler of which the bale chamber is empty there is first produced a bale whose density is insufficient. This situation occurs for example to a contractor at the start of the formation of bales on a field of a new customer after the bale chamber was emptied after finishing a field from a previous customer. This problem arises because no or insufficient crop material is present in the bale chamber to deliver sufficient counterpressure. The operator must interrupt his work after forming and ejecting the first bale, cut the twines of the first bale and process the crop a second time with the baler. This is uncomfortable and time consuming.
It is also known from for example DE4433587 to introduce an additional element in the bale chamber to generate sufficient counter pressure to the harvested material that is introduced into the empty bale chamber. These elements are impractical, time consuming and subject to wear in case of eg the inflatable body or requires a strong drive and large adjustments to the bale chamber and is extensive in the case of the rotating arms.